Improved crank for driving sewing-machines and other machinery



UNITED STATES PATENT OFEEICE.

TURNER .VILLIAMS, OF PROVIDENCE, RHODE ISLAND, ASSIGNOR TO I'IIM- SELF AND DAVID HEATON, 2D.

IMPROVED CRANK FOR DRIVING SEWING-MACt-IINES AND OTHER MACHINERY.

Specification forming part of Letters Patent No. 33,727, dated November 12, 1861.

T0 all whom it may concern:

Be it known that I, TURNER WILLIAMS, of Providence, in the county of Providence and State of Rhode Island, have invented a new and useful Improvement in Crauks for Driving Sewing-Machines and other Machinery; and I do hereby declare that the following is afull,clear, and exact description of the same, reference being had to the accompanying drawings, forming part of this specification, inA which- Figure lis an end elevation of the machine, with the end piece corresponding with A removed to show the working parts plainly. Fig. 2 is a front ViewY of the working parts, excepting the treadle, detached from the frame A. Fig. 3 is a detached view of the wheel G and rod L. Figs. 4c, 5, 6 are details which are referred to as the description proceeds.

Similar letters of reference denote corresponding parts in all the figures.

In the schedule attached to Letters Patent No. 645, granted to me, the said Turner IVilliams, and David Heaton, 2d, assignees, bearing date of March 5, 1860, a desciption is.

given of two f riction-pawls acting alternately upon two circular pathways formed upon the under side of a wheels rim for the purpose of revolving such wheel steadily in one direction, and placing the movements of the said wheel wholly under the control of the treadle. My invention in this case consists in combining the said device or an equivalent lnechanism with a crank, by means of which I am enabled to avoid the dead-center in said crank, to turn the crank always in one direction, and to limit or measure the stroke of the treadle without the aid of buers or any similar device.

To enable others skilled in the art to make use of my invention, I will proceed to describe the saine.

In the drawings the parts corresponding with those in general use for the purpose are the frame A, composed of two end pieces of cast-iron united by the rods a a o', the treadle T, swin ging upon the rod a-,the driving-wheel M, the shaft B, having a crank, B', upon one end and Supported by the hanger D, Fig. 2.

cl is the crank-pin of the crank B', formed as shown in Fig. G, to which the device above referred to is attached, and may be described as follows:

G is a wheel, (a detached View of which is shown in Fig. 5,)which is fixed upon the crankpin d at 2. Upon the crank-pin, each side of the wheel G, is placed a circular plate, it s, one of which turns loosely upon the crank-pin at 3, and the other, s, upon the hub t of the wheel G, this arrangement being convenient and simple. To the hub of each of these plates is attached a pawl, o and p, as shown in Fig. 4, by being formed with a teat which enters a hole drilled in the hub m of the plates n s. The pawls may be formed as shownin Fig. 4, having a spring, c, which serves to press the pawls into action at the proper time. A pin, O, projects from the plate, which limits the motion of the pawls and afford'sa support thereto; and the said pawls are arranged upon opposite sides of the crank-pin d and act upon the pathways gg upon the Wheel G. The plates n and s are made to vibrate upon. the crank-pin in opposite directions by means of the forked rod L, which connects the said plates with the treadle, as shown in Figs. 1 and 2, in doing which the two pawls attach themselves alternately, by a nipping action, to the surfaces g g of the wheel G; and the same movement of the treadle which causes one of the pawls to attach itself to the surface g, with which it acts, also frees the opposite pawl from close contact with its pathway g. The nipping action is produced by the binding of the pawl between the hub m of the plate and the surface g of the wheel G, Fig. 3, the said pawl being elongated in one direct-ion at r, as shown. This action may be produced as well by making the pawl in the form of a roll or a ball and forming either of the surfaces against which it acts with an ineline or wedge, the only difference being that in the first case the nipping action is due to the irregular forni of the pawl, and in the second case said action is due to the irregularity of the surface against which the regular roll, ball, or pawl acts, both being equivalent as a means for the purpose of producing the aforesaid nipping action. The end f of the forked rod consists of a spring bent in the proper form and atttaclied to the shank of the rod by a screw or rivets, the object in view being to provide for the separate action of the ends of the fork produced by the opposite vibrations of the plates 71, and s, to which said ends are respectively attached.

The several parts being constructed and arranged as above described, and the crank being in the position shown in Fig. l, upon the lower dead-center, the operation is that, the rear en d of the treadle being depressed by the foot of the operatoig'the forward end and the rod L are moved upward, which causes the pawl p upon plate s to attach itself to its pathway g, and at the same time the opposite pawl, e, to detach itself from its pathway g, in consequence of the opposite simultaneous movement of the plates n and s, as before explained, resulting from this upward movement of the treadle, which being continued, a force is exerted upon the pin 71, which being in advance of the dead-center occupied by the crank-pin, the crank is revolved in the direction indicated by the arrows until the crank-pin arrives at the upper dead-center, when the motion of the treadle is reversed, thereby reversing ythe action of the pawls and exerting the entire force of the treadle upon the pawl ein advance of the upper dead-center, which carries the crank-pin in the direction indicated by the arrows until it arrives at the lower dead-center and completes the revolution.

It will be seen that the connecting-rod L is attached to two auxiliary pins, 7L, instead of directly to the crank-pin d, as formerly practiced; that in the act of turning the crank by means of the treadle the said auxiliary pins are alternately connected and disconnected to and from the crank-pin d at the beginning of each stroke of the treadle bythe binding action of their respective pawls, the auxiliary pin in advance of the crank-pin, as the crank revolves, becoming temporarily Afixed to and performing the functions of a crank-pin, d, the action of the rear auxiliary pin, for the time, being subordinate to that in advance; that in consequence of this connecting and disconnecting of the auxiliary pins the movement of the treadle is alwats directed upon some other point of the revolution than that in a direct line with the axis of the crank, otherwise known as the dead-centers, and as the connected auxiliary pin is of necessity that in advance of the crank-pin d, the crank will be turned in butone direction.

Having described the construction and operation of my invention, I wish it to be understood that I do notlimit myself tothe precise construction and arrangement of the parts as herein described; nor do I restrict myself to the use of the peculiar frictionpawls, as balls, rollers, ratchet, hooks, &c., if skillfully arranged, will perform the alternate connecting and disconnecting function of the pawls, substantially as herein specified.

lVhat I claim as my invention, and desire to secure by Letters Patent, is-

l. Attaching the connecting-rod L to two auxiliary pins, 7i, or their equivalent, instead of directly to the crank-pin d, substantially as herein shown and described.

2. The alternate connecting anddisconnecting` of the said auxiliary pins7 or an equivalent means of attachment, to and from the crank-pin (Z of a crank, in the act of turning such crank, by means of a treadle or other device for imparting a reciprocating movement, substantially as herein described, for the purpose specified.

TURNER WILLIAMS.

.Vitnesses:

ISAAC A. BROWNELL, XV. U. POTTER. 

